The win for Lee Clark's men ended a run of 18 league games without a victory at home stretching back more than 10 months.

Blues seemed determined to put last season's woes behind them as they piled on the pressure in the opening half hour, with Lee Novak volleying wide from 25 yards and Thomas just failing to connect with Donaldson's fine cross.

Blues' long wait for a home win

Birmingham City's last league win at St Andrew's was a 4-0 victory against Millwall on 1 October, 2013

The visitors struggled to create any clear-cut chances until the stroke of half-time but Blues goalkeeper, Darren Randolph, did well to get down and save Chris O'Grady's close-range effort.

Birmingham continued where they had left off after the break, and it paid dividends on 49 minutes as Thomas put them in front with a bullet header into the middle of the goal from six yards out.

Sami Hyypia's Brighton slowly began to claw their way back into the game as Forster-Caskey's well-struck free-kick from 20 yards was saved by Randolph just after the hour mark.

After Cotterill and Donaldson almost put Blues 2-0 up, Brighton threw men forward to try and find an equaliser, but Birmingham's defence stood firm to earn them the long-awaited victory.

Birmingham manager Lee Clark: "I always stressed that we had a new group of players and I didn't think it was an issue (run without a league home victory, which stretches back to 1 October) I had to address.

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Clark on Birmingham v Brighton

"I've never spoken about it in pre-season as this is a completely new squad. I think we have seen the difference we have played.

"You have to have right players. The work ethic is brilliant. They press from the front and to win this game was brilliant for them."

Brighton manager Sami Hyypia: "We cannot take a lot of positives out of the game. I didn't like it.

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Hyypia on Blues v Brighton

"I know that we are a better side on the ball than we showed today. We couldn't get our game going.

"When you cannot score it is important to keep a clean sheet but it wasn't to be against Birmingham. I am not happy where we are at the present time after defeats against Sheffield Wednesday and Birmingham."